1. Field of the Invention
This invention relates to insulating bushings for electrical apparatus, such as a capacitor terminal, and more particularly, it pertains to a high voltage bushing.
2. Description of the Prior Art
Heretofore, high-voltage porcelain bushings have been made from wet-process porcelain, air dried, turned, bone dried, glazed and then fired. Top and bottom hardware was attached by soldering to platinum bands fired in the porcelain. Typically, the porcelain has sloped sheds for increased creepage that are turned during drawing. Shrinkage at firing has been as much as .+-.3%. The resulting large tolerances required special care in attaching the hardware that was usually secured in place by sufficient solder to produce a finished assembly. More particularly, top hardware and bottom mounting rings were attached in two separate operations with considerable cooling time elapsing between the operations. Moreover, the electrical efficiency of some bushings has not been satisfactory.